net/http: invalid header field name "js.fetch:mode"

[rudolph9]

What version of Go are you using (go version)?

$ go version
go version go1.12.8 linux/amd64

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (go env)?

go env Output

$ go env
GOARCH="amd64"
GOBIN=""
GOCACHE="/home/username/.cache/go-build"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/home/username/.golang"
GOPROXY=""
GORACE=""
GOROOT="/usr/lib/go-1.12"
GOTMPDIR=""
GOTOOLDIR="/usr/lib/go-1.12/pkg/tool/linux_amd64"
GCCGO="gccgo"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD="/home/username/project/path/go.mod"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build680907567=/tmp/go-build -gno-record-gcc-switches"

What did you do?

Attempted add the header "js.fetch:mode" so my code will work correctly in a wasm target.

However, now the amd64 target through the error:
net/http: invalid header field name "js.fetch:mode"

What did you expect to see?

it to just ignore the header

What did you see instead?

an error

Other comments

What is the best practice for handling code that is intended to support multiple build targets?

[rudolph9]

An executable that produces the can be produced with make app on https://gist.github.com/rudolph9/e3c00a0532bcbccfd1090930befb18f6

[agnivade]

Hi @rudolph9, you can use various mechanisms like build tags, runtime.GOOS and possibly other ways.

Unlike other projects, we do not use the issue tracker for questions such as these. It is only used for bugs and feature proposals. I will close this issue, but please feel free to ask it in any of these forums below:

• Stack Overflow with questions tagged "go"

• The Go Forum, a web-based forum

• Gophers Slack, use the invite app for access. The #general channel is a good starting point.

• Go Community on Hashnode with questions and posts tagged with "go"

• The golang-nuts mailing list

• IRC channel #go-nuts on Freenode

Thanks